Receptiveness to participating in cannabis research in pregnancy: a survey study at The Ottawa Hospital

Study design, setting and population

This was a cross-sectional survey study of individuals receiving obstetrical care through The Ottawa Hospital in Ottawa, Ontario. Ottawa is the second largest city in Ontario and the fourth largest in Canada. The census metropolitan area of Ottawa-Gatineau has a population of 1.3 million.¹⁴ The Ottawa Hospital is a Level 3 maternity care hospital with antenatal clinics and birthing units at two hospital campuses that provide obstetrical and neonatal care to the Ottawa-Gatineau region. During registration at The Ottawa Hospital, all patients are asked if they would like to give their permission to be contacted for future research studies through the institutional Permission to Contact program.¹⁵ For this study, individuals were eligible to participate if they gave permission to be contacted for research purposes, were 18 years of age or older, pregnant, and receiving care through The Ottawa Hospital, or if they had recently delivered and were still in hospital. Pregnant individuals receiving care at St. Mary’s Home, a satellite clinic of The Ottawa Hospital available to disadvantaged pregnant youth where clients under 18 are considered emancipated minors, were also eligible. This patient population includes youth experiencing, or at-risk for, homelessness, addictions, family and intimate partner violence, and other challenges.

In January 2020, we mailed 656 survey packages. Mailed packages included a participant information sheet, survey, pre-paid return envelopes, and a recruitment poster with a link to an online version of the survey. In this way, individuals receiving the mailed packages could complete the survey on paper or online. Recruitment posters advertising the online survey were placed in clinic waiting areas of The Ottawa Hospital and St. Mary’s Home, and postpartum wards. Using an iPad to participate in the survey was also an option for those completing the survey at St. Mary's Home. Paper-based surveys were also available alongside a secure drop-box for individuals to deposit their responses. All materials were available in both English and French. Survey responses were anonymous.

Survey

The survey consisted of 23 dichotomous (yes, no), multiple-choice, Likert scale, and open-ended questions. Respondents self-reported demographic and socioeconomic characteristics. These included age (years), race/ethnicity (Indigenous, White, Chinese, Black, Filipino, Latin American, Arab, Southeast Asian, West Asian, Korean, Japanese, Other), level of education (grade school, high school, college/university attended but not completed, college/university completed), household income (less than $25,000, $25,000-$49,999, $50,000-74,999, $75,000-$99,999, more than $100,00), marital status (married or common law; separated or divorced; single, never married; widow or widower) and obstetrical history (gravidity, parity).

Questions specific to cannabis-use covered topics including current knowledge regarding how cannabis use can affect pregnancy and postpartum health (e.g. “Do you think that using cannabis during pregnancy affects: a) your pregnancy health, b) your baby’s health, c) your breastmilk, or d) I don’t know”); and participant use of alcohol, tobacco, cannabis, or other substances (any time before pregnancy, in the current pregnancy, never). Individuals were asked if their healthcare provider had discussed the topic of cannabis use in pregnancy with them (yes, no) and to identify their primary sources for information on cannabis (friends and family; health care professionals; government websites; media, general internet searches; cannabis producers, distributors or retail providers; other).

The survey included a description of a hypothetical research study in which researchers sought to collect data and biological samples during pregnancy to explore cannabis use patterns, habits and preferences (Figure 1). After reading the description, individuals were asked how likely they would be to participate in the hypothetical research study if invited, if their partner would support their participation, and if their partner would participate themselves (answer choices: very likely, likely, unlikely and very unlikely). Questions also covered individuals’ willingness to self-report cannabis use in pregnancy and provide different types of biological samples, such as urine, blood, saliva, cord blood, newborn stool, placental tissue, and breastmilk once or multiple times throughout pregnancy. Individuals were also asked about their willingness to consent to the storage of biological samples for future use and have their data linked to their health records. Using a pre-specified, multi-select list, motivating and deterring factors for participating in cannabis-related research were captured. Individuals were asked to identify factors that would motivate them to participate the hypothetical research study described (i.e., contributing to science and health information, learning more about cannabis and pregnancy health, helping future patients, getting paid money, other), and identify any concerns they would have about sharing information related to cannabis use with researchers (i.e., being judged, feeling embarrassed, feeling guilty, being reported to child protective services, privacy concerns, changes to the healthcare they receive, no fears, other).

Figure 1. Hypothetical Research Study Prompt Given to Participants.

Statistical analysis

Descriptive statistics included frequencies (n) and percentages (%) for categorical variables. Continuous variables were described using means and standard deviations, and minimum and maximum values when appropriate. Likert-scale survey responses “very likely” and “likely” were combined, as were responses of “very unlikely” and “unlikely”.

Ethics

This research was approved by the Ottawa Health Sciences Network (OHSN) Research Ethics Board (20190529-01H). At the start of each survey, participants were provided with information outlining the purpose and nature of the survey study. Participants were informed that the survey responses were anonymously collected, and how the data would be used (including for publication), stored, and destroyed. Participants were informed that their participation was completely voluntary and that by completing the survey, their consent to participate was implied. Thus, informed consent was obtained from all participants included in this paper. Research and ethics contacts were provided to the participants in case they had any questions or concerns about the study, or about data collection or management. The OHSN Research Ethics Board reviewed and approved all study documents, including the consent process.

Consent for publication: Informed consent was obtained from all subjects.

Participant characteristics

A total of 84 completed surveys were collected between January and March 2020. Of the 656 surveys sent via mail, 16 (2.4%) were returned due to invalid or change of address, meaning 640 surveys were delivered successfully. Seventy-five (89.3%) individuals reported that they had received the survey in the mail; a response rate of 11.7% (75/640). The remaining nine (10.7%) survey responses were completed by individuals who indicated that they had completed the survey after seeing recruitment posters in-hospital or because they had been recruited by research staff. Five patients were recruited from the St. Mary’s satellite clinic. The mean age of respondents was 32.6 (±5.3) years. Sixty-six (78.6%) survey participants were Caucasian, 71 (84.6%) completed college or university degrees, 78 (92.9%) were married or common-law, and 54 (64.3%) had a household income of over $100,000 (Table 1).

Sixty-three (75.0%) individuals reported previous alcohol consumption, 20 (23.8%) indicated prior tobacco use, 39 (46.4%) reported prior cannabis use and six (7.1%) reported using other non-prescription drug use at some point before their pregnancy. When asked to indicate substance use in their current pregnancies, nine (10.7%) individuals reported alcohol use, and two (2.4%) reported cannabis use. None of the surveyed participants reported tobacco or other drug use in their current pregnancies.

Information sources and perceptions on substance use in pregnancy

A total of 67 (79.8%) individuals reported that their healthcare provider had not yet discussed cannabis use during pregnancy with them (Table 2). The three most common sources of information on cannabis used by individuals were family and friends, media (e.g., news, magazines, and social media), and general internet searches (44.0%, 39.3% and 32.1 %, respectively). Most individuals believed that using cannabis during pregnancy would affect pregnancy health (62, 73.8%), their baby’s health (70, 83.3%), and their breastmilk (62, 73.8%). 14 (16.7%) individuals indicated that they did not know if cannabis use in pregnancy would affect pregnancy health, infant health or breastmilk.

Willingness to participate in a hypothetical research study

52 (61.9%) individuals reported that they would be willing to participate in the hypothetical research study (Figure 2). 72 (85.7%) individuals said they would be likely to participate if asked to complete a survey now, and 73 (86.9%) said they would be likely to participate in doing so at other times later in their pregnancy. The majority of individuals were willing to give biological samples at the time they completed the survey or at subsequent hospital visits (55 (65.5 %) and 54 (64.3%), respectively). A higher proportion of individuals indicated that they would be willing to provide urine (62 (73.8%)) or saliva samples (61 (72.6%)) than any other sample type suggested by the hypothetical study. Individuals were least willing to consider providing placental tissue, cord blood, and newborn stool samples for the hypothetical study (>30% responding unlikely/very unlikely for each sample). Over half of the individuals reported being open to consenting to the storage and use of biological specimens for other pregnancy research (55 (65.5%)). 60 (71.4%) believed that their partners would be supportive of their research participation, though fewer (44(52.4%)) believed that their partners would also agree to be in the hypothetical research study.

Figure 2. Willingness to Participate in Hypothetical Cannabis Research Study.

Motivating and deterring factors for participating in research

The most commonly cited motivating factors for participating in research was a desire to contribute to science and health information (66 (78.6%)), and the potential for helping future patients (49 (58.3%)) (Table 3). Three (3.6%) respondents answered that there were no possible motivating factors to participate in cannabis-related research. Approximately two-thirds of individuals indicated that they had no fears for participating in this type of research (53 (63.1%)). The most commonly reported deterring factors included worries about maintaining information privacy (14 (16.7%)) and being reported to Child Protective Services (if they reported using cannabis in pregnancy) (10 (11.9%)).

Underlying data

Open Science Framework: Underlying data for ‘Receptiveness to participating in cannabis research in pregnancy: a survey study at The Ottawa Hospital’, DOI 10.17605/OSF.IO/UWDHP.¹⁶

This project contains the following underlying data:

Data are available under the terms of the Creative Commons Attribution 4.0 International license (CC BY 4.0).